DESCRIPTION: (Applicant's Description) The objective of the Tissue Core is to provide well-characterized human and animal tissues for these projects. Collection of tissues for correlative research and molecular biologic studies is a vital and essential part of gastrointestinal cancer research. In order to provide these specimens, the Tissue Core will build upon the already established Gastrointestinal Malignancy Tissue Bank (Cryobase Database System) and the Human Tissue Acquisition and Pathology Shared Resource of the Vanderbilt Cancer Center. In January 1998, these repositories together contained approximately 34 cases of colorectal carcinoma resections, providing a bank of material immediately available for projects. The mechanisms for collecting tissue samples suitable for molecular biology studies, including harvesting of DNA and RNA and biochemical analyses, are already in place. Emphasis will be placed on timely collection of samples to prevent degradation of mRNA and protein and ex vivo generation of eicosanoids. The Tissue Core will also contain a common repository of tissue specimens from animal models of colorectal neoplasia, made available by individual investigators within the Program Project Grant (PPG). The Tissue Core also includes mechanisms for histopathologic characterization and quality assurance of specimens, database management, and specimen distribution. By consolidating all histologic services in one laboratory and organizing human and animal tissues in a central database, optimal use of tissue will be possible. By utilizing a histotechnologist for tissue collection, storage, processing, cutting of blocks, and staining of slides, it will be possible to achieve high standards for all histologic studies for the project. This centralization of services under the supervision of a pathologist with an interest in gastrointestinal pathology will allow careful attention to quality assurance. Specific Aim 1: Collection of tissue suitable for PPG projects, by augmentation of existing GI malignancy tissue in the Vanderbilt Cancer Center Tissue Bank Specific Aim 2: Histologic characterization and quality assurance of tissue samples Specific Aim 3: Centralized storage of slides and animal tissues and database management